#include<stdio.h>
#include<unistd.h>
#include<sys/types.h>
#include<stdlib.h>

int main()
{
    pid_t id=fork();
    if(id<0)
    {
        perror("fork");
        return 1;
    }
    else if(id==0)
    {
        while(1)
        {
            printf("I am child, pid:%d ,ppid:%d \n",getpid(),getppid());
            sleep(3);
            break;
        }
        exit(0);
    }
    else 
    {
        while(1)
        {
            printf("I am parent, pid:%d ,ppid:%d \n",getpid(),getppid());
            sleep(1);
        }
    }
    return 0;
}
